Articles of footwear usually include an upper and a sole structure. Generally, the upper can receive the wearer's foot and secure the footwear to the foot. Also, the sole structure can provide traction for the footwear. Moreover in some embodiments, the sole structure can be resiliently compressible to provide cushioning to the wearer's foot.
More specifically, the upper can include one or more sheet-like sections of material that define a cavity for receiving the wearer's foot. The upper can also include laces, straps, buckles, buttons, and other similar components for securing the footwear to the wearer's foot.
Also, the sole structure can include a midsole in some embodiments. The midsole can include resiliently compressible members, such as foam, a fluid-filled bladder, or other similar members. As such, the midsole can resiliently compress under the weight of the wearer or due to impact with a ground surface. This can help distribute the resulting loads across the sole assembly and/or attenuate the loads to provide cushioning.
The sole structure can additionally include an outsole. The outsole can be made from relatively high friction material such that the outsole can readily grip the ground with firm traction. The outsole can also include grooves, sipes, recesses, or other features that increase surface area of the ground engaging surface, that can channel water away from the ground engaging surface, or otherwise increase such traction for the article of footwear.